Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
Volume:9 Issue: 2, 2016

Heat Transfer has special importance in engineering applications. So, researchers have suggested different new idea to increase heat transfer and using nanofluid is one of these methods In recent years, new methods have been used. One of these methods is the use of nanofluids, ., because nanofluids have higher heat transfer potential than base conventional fluids. In this investigation effect of suspended CuO nanoparticles with volume fraction of 0.005 into base water fluid is considered under turbulent flow regime inside double tube counter heat exchanger. It was observed that suspending pre-mentioned amount of nanoparticle augmentate heat transfer capability of conventional water fluid. On the other side, it leads to increase pressure drop and friction factor of water base fluid. Finally they conclude that positive effect of heat transfer augmentation is so stronger than negative effect of increasing pressure drop and friction factor that motivate to utilize this nanofluid in practical applications.

Building the Nano composites for getting material with combinational properties and improving properties of currently used material has been taken significant attention. One of the ways of building Nano composites is using a method known as powder metallurgy. Because with this method not only wastes are decreased to minimum but we can also mix the materials with high melting point with the materials with low melting point which is a difficult thing to do with foundry method. In this research titanium alloy for improvement in its mechanical properties is mixed with silicon carbide reinforcing. Knowing the fact that silicon carbide is in Nano scale these two materials start building Nano composites. The powder metallurgy method is the best way for mixing these two materials together. To make sure that the properties of the made alloy is similar to the foundry alloy, the static compression methods are used. For comparison the results, two factors such as the Nano silicon carbide percentage and the static compression pressure are. Also, Density experiment, observation of grain boundaries using a scanning electron microscope, pressure test and the hardness experiment was done on it.

In this paper, modeling of high speed projectiles with different nose shapes, penetrating into steel fiber reinforced concrete is investigated. This is a novel study because it considers the length to diameter ratio of steel fiber as well as projectile length to diameter ratio and volume fraction of fiber used in concrete matrix on the impact resistance of steel fiber reinforced concrete fibers at high speeds. Numerical simulation is used using LS-DYNA explicit code. The projectiles have an approximate mass of 45 (gr) and their velocities are about 2500 (m/s) penetrating into steel fiber reinforced concrete panel with volume fraction of 1.0%, 1.5% and 2.0%. In this article the exact behavior of steel fiber reinforced concrete confronting metallic projectiles at high speed is predicted. The results of the simulations are compared with experimental work of other investigators and, the results show that ogive nose projectiles are more efficient than other projectiles. In other words, by increasing the projectile length to diameter ratio from 0.5 to 0.9, for flat, hemispherical and ogive projectiles their residual velocities are increased. Also, it is shown that by increasing the volume fraction of steel fibers in concrete matrix, damage of top surface damage is reduced dramatically. The analytical model presented in this paper considers the speed variations of the projectile during the penetration process into steel fiber reinforced concrete is an important achievements this respect.

The use of natural gas as an alternative fuel, in recent decades has been proposed. Good combustion properties and cats less than it could be the perfect choice for the next generation. Simulation models can be of great help engine designers. Simulation models to reduce the time and costs for the development of new engines as well as in identifying the technical value that need special attention in the design, are of great importance. In this study the thermodynamic model for the study of thermodynamic parameters of a spark ignition engine fuel mix methane (C2H6O) and ethanol (CH4) is provided. To simulate the engine, the governing equations for modeling the area of combustion engines can be used. This relationship has become in MATLAB code, and finally by drawing diagrams, are analyzed. The results showed that the addition of ethanol to fuel higher percentages of methane, increasing amounts of pressure inside the cylinder, work and heat output (power stage) as well. However, the energy lost through leakage and most pure methane lowest temperature of the burned area is capable.

One of the biggest problems of artisans , is notching the high speed steel roller is due to the inability to do this work, become high speed steel roller bearings are disposable. One of the biggest problems of artisans , is notching the high speed steel roller is due to the inability to do this work, become high speed steel roller bearings are disposable.When the roller is placed on the production line, because of the retained austenite make it very hard. High speed roller used in this study is barely above 70 Shc. Our goal is to obtain the optimum machining parameters that it requires a high number of tests that are practically impossible. So in order to achieve optimal machining parameters with the lowest test, RSM method in Minitab software was used. CBN tools performed well in all tests and succeeded with the best cutting speed 25 m/min, 0.05 mm feed and 0.05 mm depth of cut at the time of 1080 seconds, in notching one caliber.

Given the need to increase the efficiency of heat transfer in thermal systems, especially systems using nanofluids in microscale and nanoscale heat transfer equipment ideas to improve their performance is very good.In present study, the flow and heat transfer of Water-Cu nanofluid in micro-tube with slip regime with constant wall heat flux numerically simulated with low Reynolds numbers. Slip velocity and temperature jump boundary conditions are also considered along the microtube walls, for first time. The results are presented as the profiles of temperature and velocity. Nusselt number and pressure drop coefficient calculated in interance and full developed region. The effect of slip and using nano particle considerd.
It is observed that Nusselt number increases with slip velocity coefficient and pressure drop coefficient decreases; att intrance region the Raynolds of flow has effect on Nusselt and pressure drop coefficient,too.
Likewise observed nano particle adding to water has low effect to increases Nusselt number and pressure drop coefficientt.

Metal coating, metal materials are of two or more layers. The coating metals are widely used in industry. These sheets or saving performance and cost effective solution or both the user. Performance coating metals according to usage in structural applications, settings thermal expansion of the thermo-mechanical control (thermostat), electrical, magnetic, corrosion resistant, flowering and decorative connection is divided. In each action, you may have attended several coating metal system.
In this study, using the process connectors, three-layer aluminum sheet net aluminum, stainless steel was producedd Magnesium-. Examples of cross-links in different situations rolled and annealed photos were taken. In order to determine the best conditions for the production of multi-layer sheet, the effect of process parameters were evaluated connectors. Changes in different mechanical properties by tensile test was performed according to ASTM E8M allowed. The survey showed that the samples annealed at temperatures above 375 ° C for aluminum, a substantial increase bond strength of the samples has been rolled.

Nanofluid is prepared through the nanoscale particles suspended in a fluid base and Nanotechnology is a new attempt to investigate the thermal sciences. As a result of huge investment in developed countries on nanotechnology, research on thermal properties of nano-fluids is of particular interest.Due to the usage of nanotechnology to reduce energy waste, in this project CeO2 with EG is used to prepare the nanofluid. For stabilization of nanofluid ultrasonic wave is used and viscosity is measured by digital viscometer. In this paper, the effects of temperature and volume fraction on viscosity of nanofluids are considered. This study indicated that the viscosity decrease in all concentrations when temperature is increasing and it increases with additioning volume fraction of nanoparticles. Also, the results show that viscosity changes related to temperature at higher concentrations. After deliberation of rheological properties and laboratory characteristics the exact formula for nanofluids viscosity obtained according to temperature and volume fraction to high accuracy.

Free convection flow in an enclosure filled with a congealing melt leads to the product with a nonuniform structure involving large grains. The convective flows are decreased by applying an appropriate magnetic field, obtaining uniform and small grain structures. In this work, using the finite volume method, we investigated the application of a magnetic field to the convective heat transfer and temperature fields in steady and laminar flows of melted gallium in an annulus between two horizontal cylinders. The inner and outer walls of the annulus are hot and cold, respectively. Moreover, the effect of the magnetic field on the flow and temperature distribution has been investigated. The influence of the variation of other parameters including the Rayleigh number and the angle of the magnetic field on the flow and temperature field also have been studied. It has been revealed that on changing the field angle to the horizon, the Nusselt number (Nu) is increased, which is of importance in a specific range of Hartmann numbers. Also with increasing the Rayleigh number, the change in Nu with the magnetic field intensity does not occur.

In this study, the behavior of nanoparticles using a numerical model is discussed. For this study a model for the expansion in free convection heat transfer and mix in a rectangular container with dimensions of 1 × 4 cm using Nano-aerosols in the air is going when copper nanoparticles, use and by changing the temperature difference between hot and cold wall, we will examine its impact on the rate of heat transfer. The simulation involves two-dimensional flow simulation and relaxed state of constant flux in free convection on the two lateral sides and on the top face of constant temperature (cold plate) at 300 K was considered And at low temperature (heat plate) in three modes 350, 400 and 450 K were compared. Temperature distribution, velocity, surface heat flux and Nusselt number during the course of our review.Finally, enhanced heat transfer in the presence of copper nanoparticles and changes in the temperature difference between warm and cold wall was observed

In this paper, Asymmetric buckling analysis of functionally graded (FG) Circular plates with temperature dependent property that subjected to the uniform radial compression and thermal loading is investigated. This plate is on an elastic medium that simulated by Winkler and Pasternak foundation. Mechanical properties of the plate are assumed to vary nonlinearly by temperature change. The equilibrium equations are obtained using the classical plate theory (CPT), Von Karman geometric nonlinearity and virtual displacement method. Existence of bifurcation buckling is examined and stability equations are obtained by means of the adjacent equilibrium criterion. The effects of elastic foundation coefficient, thickness to radius, power law index, and temperature-dependency of the material properties on critical buckling load of FG plates are presented. The results of the present work have been compared with the results of other investigator and the results of the comparison are very good. It is found that by increasing temperature, critical buckling load decreases. It is also concluded that the critical buckling load of (FG) Circular plates increases with an increase in the Winkler and Pasternak constants of elastic foundation.

The main purpose of this article is the structural analysis of a composite blade of a selected helicopter. In this study, the stresses on rotor's blades caused by centrifugal forces, lift, drag and torque are analyzed. The governing equations of the structure behavior and solving processes were carried out by MATLAB software, and simulation is carried out by ABAQUS software, and they are compared with each other. The program written for MATLAB is based on beam element theory and the computation of stress and displacement of considered elements of a blade, is one of the properties of the written code. In ABAQUS, the helicopter blade is simulated in various states such as composite and aluminum blade with/without web and composite blade with laminations in different angles. The results of the mentioned states are compared with each other and with the code and finally, the results are compared with reference article. Comparison between beam element results and ABAQUS simulation shows proper match. In order to optimize a composite blade, attention must be paid to factors such as, displacement and stress reduction and prevention of excess in weight, as by an increase in thickness of 45 and 90 degree laminates to 6.5 mm, maximum displacement would be 12.9 cm, and total weight of the structure would be 8 Kg.

In the present paper, electrical energy harvesting from random vibrations of an Euler-Bernoulli nano-beam with two piezoelectric layers is investigated. The beam is composed of an aluminum layer together with two piezoelectric ceramic layers (PZT 5A) serving as energy harvesting sensors. In the proposed method, the equations governing the bimorph nano-beam will be analytically derived using classical beam theory with corresponding modification coefficients to the nano-structure applied. Then, the derived system of equations will be solved following Kantorovich method. Assumed boundary conditions for the nano-beam are as follows: a clamped end with the mass concentrated at the free end of the beam. Further, the input activation function of the system for energy harvesting was taken as being random. Since the objective of this research is to investigate the amount of harvested energy, the section on the results provides associated voltage and maximum output power curves with the bimorph nano-beam under random activation and input white noise, while also presenting the effects of characteristics and scale factor of the nano-particles on the amount of harvested energy.

In the present research, the mixed-mode fracture mechanics analysis in a plate with central hole under tensile loading is considered. It is assumed that a plate containing two symmetrical hole-edge cracks is bonded with two dissimilar planes. The stress intensity factors at the crack tips are calculated. The problem is modeled in Casca software and this model is analyzed with Franc software. The effects of various factors such as hole diameter, crack length, angle of crack and material properties of plates have been investigated on stress intensity factors. The stress intensity factors increases with increasing crack length. Also, the stress intensity factors increases with the increase of hole diameter. For a certain amount of for small crack lengths the effect of cracks length on variation of stress intensity factors is more than the hole diameter but for large crack lengths the effect of hole diameter on variation of stress intensity factors is more than the cracks length.

Electromagnetic power, which is one of the fast ways for forming, is used for forming workpieces without having any effect on them. Using it causes the workpieces to reach the minimum back spring and tear; consequently building the equipment like pistons will cost less than before. Electromagnetic power is used for forming Aluminium sheets into V shapes in this study. As the coils connect the machine and the workpieces, the number of rounds and the voltage in 10 levels will be discussed in this study. Considering the results and analysis that have been reached, the best forming occurs in the voltage of 1500 and 35 rounds. Because the machine creates a high ampere and a proper amount of rounds in this voltage in order to transfer the whole power to the workpiece. As the rounds increase to 40, the forming will decrease up to 34/3 percent